An Extremely Low Probability Event
by Forthwith16
Summary: Lelouch has questions for Kallen. He has his geass to get his answers. Kallen is a time traveller.


**A/N:** If you're waiting on the next chapter of my HP story, it'll be out in about a week. In the meantime, feel free to enjoy this Code Geass fic. Part of me wants to write a proper time travel story, but I always stumble across the awkward question of _why_. They're fun, certainly. I've read and enjoyed more than a couple. But it's so easy to let them just be a feel good kerb stomp or a rehash of canon with few changes. Anyway, enjoy.

* * *

Lelouch narrowed his eyes as he watched one Kallen Stadtfeld eating with a few of their mutual classmates. He knew that face. He knew that expression. She was wearing a mask. She was hiding in plain sight.

 _Just like I am._

Now Lelouch just needed to get Kallen alone to confirm his suspicions. He had no intention of casting his geass upon random civilians if he could help it, so that option was out. The buzzing of a bee caught his attention. A frown overtook him as he considered an odd thought.

 _I suppose it's worth a try._

Bringing forth the power of his geass, Lelouch looked into the bee's eye. "Go chase the red-haired girl away from the others."

To Lelouch's surprise, the bee flew off toward Kallen and her classmates. Everyone but her immediately shot to their feet and ran off. She, on the other hand, rose slowly, radiating her displeasure. Whether it was with the bee or with continuing her act, Lelouch could only guess.

Finally, though, Kallen was alone. And from the way she slashed the bee out of the air with nothing but the flat of her hand, Lelouch knew he'd found the rebel devicer from Shinjuku. Having witnessed her abilities firsthand, he knew a good opportunity when he saw one. He _had_ to have her skills. She easily qualified as an Ace. She'd even managed to go toe to toe with that white knightmare for a few seconds despite being horrendously outmatched technologically, saving his life in the process.

So it was that Lelouch approached Kallen.

"Can I help you?" Kallen asked. Considering that Lelouch had just caught her breaking character, she sounded rather more irritated than nervous. More important, however, was her utter lack of even the briefest of eye contact. She'd turned her attention away and back to her sandwich before he even said a word.

Frowning, Lelouch said, "I was hoping to ask you a few questions, but if I'm interrupting…"

"Uh-huh," Kallen said through a mouthful of sandwich. She swallowed. "Let me answer all the questions boys ask me in order. No, I'm not dating anyone. Yes, it's hot today; it's not just you and or me. Speaking of…" Kallen withdrew a pair of sunglasses from her skirt and placed them on her face. "Yes, I have heard better pick-up lines. And lastly, no, I'm not interested in dating a total stranger, but we could give friends a try first if you're interested in me beyond my looks."

"That's…not actually what I wanted to ask you." Really, what was Lelouch _supposed_ to say to something like that?

"Well, good," Kallen said. Her expression relaxed into a slight smile, and she turned to look at Lelouch.

Activating his geass, Lelouch took a chance that it would work through sunglasses. "Please answer my question."

"You'd have to actually get around to asking it, first, you know," Kallen said. "Then I can decide if I will."

Lelouch quietly clicked his tongue. _I need an excuse to get her alone inside._ Searching his mind, an idea occurred. "As you've been gone awhile, I should inform you that I'm the Student Council Vice President. Everyone at Ashford Academy is required to join a club. I was wondering if you had one in mind, now that your health is returning."

"Ah," Kallen said, drawing out the sound in understanding. She nodded. "I understand. You're looking for more warm bodies to put between yourself and Milly Ashford, aren't you?"

Despite himself, a snicker escaped Lelouch with a smile. "It _is_ accepted tradition to sacrifice beautiful females to evil gods."

"And that has to be just about the strangest line I've ever heard."

"I didn't mean–"

"I know," Kallen said, interrupting before Lelouch could explain himself. "If the Student Council won't mind my numerous absences, then I suppose you can consider me your virgin sacrifice."

"Excellent. I'll collect you after class tomorrow. Our next meeting will be then. Knowing our illustrious president, you can expect a party lasting into the night."

* * *

Lelouch had grown desperate. He could admit that to himself. Suzaku's 'trial' for the assassination of Clovis loomed ever closer. He _had_ a plan, but he needed at least two assistants to pull it off properly. Preferably, he would use _willing_ assistants, but catching Kallen alone had proved…difficult. For some reason, there was always _someone_ around her. Either that, or they were outside and she continued to wear those infuriating sunglasses which he knew perfectly well _were not prescription_ , all protestations to the contrary ignored.

In all honesty, Lelouch suspected Kallen found the situation amusing, although for the life of him he couldn't figure out how that could possibly be the case.

And so Lelouch had taken fate into his own hands. He'd done the unthinkable. He'd given Milly an idea. A half an hour after being dressed up as a girl for a genderbent party himself, it was Kallen's turn to suffer. Milly had tied her down to a chair to work her most terrible magic, and that was all the opportunity he needed.

Lelouch looked Kallen dead in the eye and activated his geass. Her eyes widened as he said, "Answer my questions honestly and fully until you are untied from this chair." Then to everyone else, he commanded, "Kallen has fallen slightly ill and is to be left in my care for the night. Go celebrate without us, lock the door behind you, and don't return until tomorrow."

Once everyone was gone, Lelouch breathed a sigh of relief. _Finally! This shouldn't have been so hard!_ He turned his attention back to Kallen, who remained under the thrall of her order. _I swear, if she_ wasn't _the devicer from Shinjuku…_

Lelouch shook his head and began his questioning.

"Were you the pilot of the red glasgow in Shinjuku not long ago?"

"Yes."

 _Good. This wasn't all for nothing._ "What was your goal in stealing that canister from Britannia?"

"We received intel that it was poison gas intended to be used to cleanse the ghettos. We stole it to prevent the immediate threat. One of our members used to be a chemist and hoped to develop a counteragent. Some of us hoped that exposing the gas internationally would get Britannia in actual trouble for breaking the international ban on possession of chemical weapons."

"I see." It was good to know that the group this Ace devicer belonged to at least had a bit of sense and morality to them. Before he moved onto the more weighty questions, Lelouch decided to satisfy his own curiosity. "You're Britannian. Why are you involved with a terrorist cell against Britannia?"

A very long silence stretched on, one not typical of Lelouch's admittedly limited experience with his geass. He was about to say something when Kallen finally answered.

"Because they will become the Black Knights."

Of all the answers Lelouch expected, this one came right out of the blue. _The Black Knights? As in the historical knights that fought without heraldry or liege? Wouldn't ronin be a more apt word here in Japan?_

Shaking his head, Lelouch put his own thoughts aside for the obvious solution to his questions. "What are the Black Knights?"

"The Black Knights will be heroes of justice who help the weak against the tyranny of the strong." Even through the geass, a strange mixture of pride and disgust came through in Kallen's voice.

"Huh?" _What even–_ "Is your group trying to be a modern day Robin Hood?"

"No."

Lelouch tried to suppress his growl of frustration. "Elaborate." When no answer proved forthcoming, he smacked a hand to his forehead. "What do you mean by no?"

"Our group is the remnants of my older brother's organisation. The Black Knights are founded by Lelouch vi Britannia as Zero."

A moment passed.

"What!" There was _no possible way_ Kallen could know about his idea to pose as a masked vigilante named Zero and, as him, to claim the credit for Clovis's death. It was impossible. And yet here she was. "How do you know about my Zero persona?"

"I was your closest, loyalist, and strongest knight until you pushed me away to save my life." Again, pride came through in that answer, rather than the usual monotone of someone under a geass.

For his part, Lelouch slumped over onto a chair. _Okay. Either Kallen is completely mad, or…there are other geass users interfering._ "When did I push you away?"

Another moment passed in silence before Kallen answered, "Over a year from now."

A thought occurred. "Are you a time traveller?"

"Yes."

Well, that settled that. "How did you time travel?"

"My geass…" Kallen trailed off uncertainly.

"Do you not know how it works?"

"Yes."

"Have you used it more than once?"

"No."

"I see…" And suddenly life had become infinitely more complicated. There _was_ a bright spot, however. "Are you still loyal to me now?"

"Yes."

"Why?"

"Because we both wish for a more peaceful world, because you have the political and military skills necessary to see that dream realised, and because I'm in love with you."

And it was just one blow after another today. "Why did you come back in time?" There was one particular answer Lelouch was dreading.

"You martyred yourself as the demon emperor of the world to bring about peace. I wanted to save you."

Lelouch opened his mouth, but no words came out. He tried again. " _Was_ there peace?"

"Yes."

"So you destroyed a peaceful timeline – an entire peaceful reality just to save me?"

"Possibly. I left one, certainly, to save you, and my mum, and Shirley, and Shirley's father, and–"

"No, stop. That's fine," Lelouch interrupted. While he had no doubt that he was Kallen's _primary_ motivation, at least she didn't sound _too_ obsessed. "What will you do if I don't fall in love with you?"

"Try to move on."

 _That's it?_ Lelouch had expected Kallen to want to loop time until she got what she wanted. "Why did you come back to save me if you're okay with letting me go?"

It took a few seconds before Kallen answered, but she did. "Your death was very traumatising for me. I could have prevented it if I'd not let you push me away. I knew something was wrong, but I followed your unspoken orders to stay put and fight against you. _Not_ saving you when I could would have broken me entirely."

Lelouch breathed deeply, not entirely sure how to deal with the situation in front of him. _Stick to business, Lelouch. Stick to business._ "How strong are you in a knightmare?"

"My skills are on par with Suzaku Kururugi and Bismarck Waldstein, both of whom cheat."

His brows furrowing, Lelouch asked, "How do they cheat?"

"You geassed Suzaku to live. He abuses the command to boost his reaction time. The Knight of One has a geass that lets him see into the near future."

"He has a…" Lelouch breathed deeply once more. "Who do you know possesses or has possessed a geass?"

"Lelouch vi Britannia, Kallen Stadtfeld, Bismarck Waldstein, Mao, Rolo Lamperouge, Marianne vi Britannia, Charles zi Britannia–"

 _Shite! Shite! Shite!_

"–George Washington, Napoleon Bonaparte, C.C., Vincent zi Britannia, Alwin the First, and several thousand members of a geass cult under the emperor's control."

The silence stretched on before Lelouch concluded that, really, business could wait. He had a world class devicer in love with him to sort out. While not exactly higher priority, Kallen was a much more immediate and entirely less terrifying concern.

"What were you doing before you came back?"

"After finishing comprehensive school at Ashford, I left Japan with Mum for Britannia. Officially, I was Nunnally's Knight of One, but I was unofficially retired from active duty. I spent most of my time advising her, reconciling with my dad, and avoiding Gino Weinberg."

It took Lelouch a little while to find his voice. "Nunnally was the Empress?"

"Yes."

"Britannia accepted a blind, crippled girl as their ruler?" It sounded too good to be true. How could such radical change come about in a mere year or two?

Another pause as Kallen considered the question. "I think they would have."

Confused, Lelouch asked, "What do you mean?"

"Nunnally isn't blind."

No words came to Lelouch.

 _Nunnally can see? But how?_ "How did she regain her sight?"

"She broke her father's geass when confronting you during the final battle."

"That bastard _purposefully_ blinded my sister! I'll kill him! Why did the emperor geass my sister?" Lelouch demanded.

"Nunnally believes it was to cover up the attempted murder of your mother."

"...what?" _My mother is alive?_ "Is my mother alive?"

"Yes."

It was too much. Lelouch needed time to process everything. Was everything about his life a lie? How did he become the emperor if his father was…still a complete and total monster?

"How did I become emperor?"

"You geassed the imperial court to recognise you after you asked God to kill your parents."

"What? God? My parents… I… What?"

Kallen had no response to such an open ended question, and to be perfectly frank, Lelouch felt unable to take whatever other secrets might spill out of her mouth.

"Were you planning to tell me any of this?"

"I was undecided," Kallen replied. "I was unsure how to get you to both take me seriously and not kill me the moment I said the word geass, much less trust me."

After a second, Lelouch said, "Fair." Another second passed in silence. "Are you going to take any action against me after I release you?"

"It will take me perhaps three seconds to realise you used your geass on me and grow angry. If you let me know that you know I know about geass, then I will probably punch you."

 _Well, I suppose I'll probably deserve it._ "Is there anything I could do to prevent that?"

"A sincere kiss would likely delay and lessen my wrath."

Lelouch sighed. _Might as well get this over with._ With great reluctance, knowing he was going to be punched in the face and knowing it was going to hurt, he unbound Kallen. He watched the geass fall off of her, and as she'd said, mere seconds passed before realisation showed so clearly on her face.

"I'd really prefer it if you not hit me. At least you're immune now, right?"

Kallen punched Lelouch.

* * *

After visiting the bathroom to clean up the black eye Kallen had given him, Lelouch returned with an ice pack held against it. There he found her sitting at the head of the table, one leg crossed over the other, her arms folded and an imperious glare in her eyes. The message was clear.

 _Great. I'm dealing with a pissed off Knight of One._ Lelouch opened his mouth to apologise, but Kallen saw right through him.

"Save it," Kallen said. "You're not sorry, and you only want to placate me. I _will_ take solace in the fact that you can't do it again, but _only_ if you tell me _exactly_ what you did to me."

Lelouch opened his mouth.

"If you lie, I _will_ make you beg for the merciful release of death."

With a grunt, Lelouch stood up straighter. "I wasn't going to. There's apparently no point in doing so with you. I only asked you a few questions."

"I see." Kallen _looked_ rather unimpressed, but there was relief buried deep within her tone. "And what did you find out?"

"Enough to wonder what sort of fantasy world we live in. I stopped asking questions when you started talking about God killing my parents at my own request."

"Ah…" The sternness in Kallen's face faded at the change in topic. "Yeah, Suzaku was kind of vague on that nonsense. I'm not sure if either of you knew what was really going on with that. Something about Ragnarök and an assimilation plot."

"Well, we have a year at least before we have to deal with it. For now, let's stick to matters that don't make me want to throw my hands up and leave the planet."

Lelouch chose a chair near Kallen, pulled it away from the table, and sat down so that she would have to turn toward him. Petty, yes, he could admit that, but rather this than sitting at the other end of the table and having to shout at each other to be heard.

"So you were my sister's Knight of One?" After Kallen nodded, Lelouch asked, "How did you get that job?"

"It's funny, really. You had me transferred to the position while you had me imprisoned. I only learnt about that when Nunnally came knocking at my door asking me to, and I quote, please come into work for once."

That pulled a smile out of Lelouch despite himself. "That sure sounds like Nunnally. Before our mother died, of course."

Kallen quirked an eyebrow. Lelouch rubbed his forehead.

"Look, I've spent the last seven years believing my mother was dead. Please spare me the criticism."

"Fair enough."

 _Anyway, if my future self entrusted Nunnally to Kallen, I suppose I might as well consider her beyond mere matters of trust. And as the Knight of One, I imagine she's used to a certain degree of sovereignty that she'd be unwilling to give up in its entirety._

"I assume," Lelouch began, "that you're not eager to work for me but will work _with_ me."

"A wise assumption. I know you well enough to see through your lies, and I _will_ smack you down if you lie to me for no reason."

"Fair enough," Lelouch said, echoing Kallen's earlier words. "I expect not to be lied to in turn."

" _I'm_ not the pathological liar in this relationship, but alright."

Lelouch paused a moment, deciding if he _really_ wanted to breach _that_ topic. _It's going to come up sooner or later…_ "About our…relationship."

"You asked about that, too?" Kallen said, incredulous. "Do you have _no_ concept of privacy?"

"I did no such thing! You mentioned it when I was asking an entirely…tangentially related question. Regardless, I didn't pry."

"Fine. Say what you want."

"I'm not the Lelouch you feel in love with."

"I know that," Kallen said, and everything about her face and body language agreed. "You're very close, but you're still an arrogant boy out for revenge who thinks everyone but his big brother Schneizel and father is an insect beneath him to be squashed."

Gritting his teeth, Lelouch let his temper settle before speaking. "I take it I lost a few times."

" _Hard_ ," Kallen said without a hint of hesitation. "I'm almost tempted to let the small losses happen just so you can learn your lesson."

"I'm sure we can find an alternative." Wanting to put _that_ topic as far behind him as possible, even for another dangerous topic, Lelouch asked, "So what exactly were you and my future self?"

Kallen sighed in exasperation. "I'm not sure. You were at least my friend. Every time we almost had a moment, someone would interrupt us. I finally managed to kiss you once, but you were already suicidally depressed at that point. The only other woman close to you was C.C., but she wasn't–"

"Who?"

"Oh, your witch hasn't shown up yet." Kallen then mumbled, "I wonder if she's at my place."

Catching on, but with his willing suspension of disbelief cracking, Lelouch asked, "C.C. is the woman who gave me geass?"

Kallen nodded. "Mine, too."

"I don't know what happened in your timeline, but she was shot in the head in this one."

Kallen waved her hand dismissively. "That's just a flesh wound. She'll be fine."

Lelouch hesitated a moment. "How?"

"She's immortal in the ageless, unkillable sense. You can still shoot her and chop her up into fine bits, though, to inconvenience her."

Lelouch opened his mouth then closed it. "I don't know what I was expecting."

"Fair warning. She's…aggravating."

"Right… Milly?"

Kallen nodded. "Less harassment and more cryptic nonsense, but about as bad."

"Fantastic. Anyway, you were saying?"

"Hmm? Oh. Well, the only other woman close to you was C.C., but that was never romantic, no matter how much she liked to tease me about being your mistress."

Silently, Lelouch cursed whatever god apparently existed in this world.

"Shirley has a huge crush on you, but she doesn't know the real you beneath all those masks you wear and isn't… What's the right word? Strong enough, I guess, to deal with your life. Besides, the last time through, us killing her father, you altering her memories, the emperor altering her memories, and your yandere, fake brother killing her sunk that ship over and over."

"I can't describe how much I don't want to know the story behind that beyond ensuring none of that happens."

"I'll tell you what's relevant when it comes up. Anyway, the only other girl who'd been 'in the running' would be Kaguya."

"Kaguya Sumeragi?"

"Yeah. Don't think too deeply about it. She's the self-declared future wife of Zero and leader of your harem, which consists of her, C.C., and me."

"Why is it that the more you tell me about my future the more I think it's not worth it?"

That only made Kallen laugh at Lelouch's misery.

"Fine. Just… Look," Lelouch said. "I'm going to be frank. The idea of a proper relationship hasn't honestly occurred to me in anything more than a passing fancy since I understood what girls were. Finding someone I could trust, who would keep my secrets, who wouldn't balk at my ambitions, who wouldn't feel like wasted time when I could be doing something productive, and so on seemed both impossible and not worth the risk.

"Now you fall into my lap, and I have no idea what to do with you. On the one hand, having an official love interest will apparently make my life simpler and less frustrating. On the other hand, _I_ don't know a thing about you, let alone trust you with anything without first telling myself I can. Where do we go from here?"

"Well _, my_ plan," Kallen began, "before you derailed it tonight, was to be your friend and help you grow up, then deal with a more mature version of you who'd internalised that I _am_ all those things."

Although Lelouch was growing increasingly irked at being treated like a child, which he begrudgingly admitted he was in comparison to however old Kallen was, he could admit to himself that her approach sounded reasonable, if no longer practical.

"That said, I do agree that if we were publicly known to be dating, our lives would be much simpler, and our simultaneous absences would be much easier to explain. You have no idea how much of a headache that became. We both independently ended up planning to graduate early, but events conspired against us."

Lelouch let that information stew in his brain as he considered the best way to proceed. Eventually, he said, "Alright, how about this? We let the rumour mill turn on its own. If anyone asks, we admit we're dating but don't want to make a spectacle of ourselves. In private, we can be…accomplices and friends, and wait to see if that goes anywhere."

"I can live with that."

"Good." Lelouch went to ask about how his plan to free Suzaku went, but if he was going to be publicly connected to Kallen Stadtfeld, there was another question that needed asking first. "How well known are you as a member of the aristocracy?"

"At this point, not very. My stepmother considers me a disgrace and rebuffs the usual offers of marriage and such. Granted, my dad despises arranged marriages so much that he'd turn them down _anyway_ even if they came from the emperor himself, but I'm pretty shielded. I was only identified last time because Suzaku outed me."

Before Lelouch could ask why Suzaku would do that, Kallen pressed on. "A word of warning. We're not going to get along with Suzaku. Probably not ever, since I intend to subvert everything that broke his naive idealism."

"Are you seriously telling me he won't learn his lesson after being so blatantly framed to push an agenda of oppression?"

Kallen sighed, which said everything for her. "He's very set on changing Britannia from within. Unlike you, killing his father was not a welcome–"

"Wait. What?"

"Oh, I thought you already knew. Yeah, Suzaku killed his father to end the Second Pacific War. It really messed him up."

Lelouch collapsed backward into his chair. "How do you know all this?"

"Well, some things I found out when I told everyone I was going back in time. There were a few secrets being withheld from me until then. But mainly I'd made it a hobby of mine to write an accurate history of the life of Lelouch vi Britannia including all the supernatural nonsense and what context I could gather from before your birth. I'd planned to publish it when I died."

Shrugging, Kallen continued, "I don't know how well it'd have been received, but I at least wanted people to be able to judge you for yourself, rather than the monstrous tyrant you presented to the world at the end. I was still debating on the title. I'd narrowed it down to _The Consummate Liar_ , _K-1_ , or _Code Geass_ , though."

Lelouch held up his hand. "I'm going to stop you right there." He stomped down on the actual attraction he felt for someone who would put that much effort into something he probably didn't deserve before wondering if doing so was counterproductive.

Regardless, Lelouch shook his head. "As much as I'm sure you'd enjoy talking about your hobby, we're rather pressed for time. Suzaku's trial and probably execution is tomorrow."

Although she looked a bit miffed, Kallen nodded. "Let me tell you what happened, the immediate and distant consequences, and how we might change things."


End file.
